The present invention relates to an image correction system including an image capturing device and a correcting method for image data.
JP-A-2001-268429 discloses an image capturing apparatus. This image capturing apparatus includes a hand-shake detection section for detecting hand-shake of the image capturing apparatus; a motion picture mode correction level computing section for computing the amount of correction on the movement of an image in the motion picture photographing mode on the basis of the hand-shake detected by the hand-shake detection section; and an image movement correction section for correcting movements of the image on the basis of the image movement correction level computed by the motion picture mode correction level computing section.
As described in JP-A-2001-268429, in relation to a motion picture, blurs in a picture attributable to hand-shake can be corrected on the basis of the hand-shake detected by the hand-shake detection section.
For instance, angular velocities detected by a gyro sensor or the like are stored in memory along with a plurality of continuously-captured frame images. The position of each of the frame images within a picture frame is moved in a direction to cancel the amount of deviation computed on the basis of the stored angular velocities. Thereby, hand-shake is considered to be canceled.
However, there may be a case where merely storing in memory data pertaining to angular velocities detected by the gyro sensor results in a failure to appropriately cancel the hand-shake arising during capture of a plurality of frame images. An example of such a failure will be described below.
When hand-shake, which has arisen between a first frame image and a second frame image immediately subsequent to the first frame image, are canceled, angular velocities, which have been detected during a time period in which two frame images are being captured, are subjected to integration. The second frame image is moved within the picture frame thereof by an amount corresponding to the integral value, to thus enable cancellation of hand-shake. Thereby, an object appearing in the first frame image and another object appearing in the second frame image can be aligned to essentially the same position within the picture frame.
However, when acquisition of angular velocity data performed by a gyro sensor and acquisition of a frame image are performed independently of each other, storing angular velocity data detected by the gyro sensor into memory is not sufficient to identify the nature of angular velocity data—among a plurality of pieces of angular velocity data stored in the memory—detected during a time period between the first frame image and the second frame image, making it difficult to accurately perform hand-shake correction.
Especially, when data pertaining to a frame image captured by an image capturing device are temporarily stored in a buffer, such as video memory, and when the data are captured at a predetermined frame rate from the buffer to predetermined memory, a delay arises between the former capturing timing and the latter capturing timing. Accordingly, the above-described problem becomes particularly noticeable.